Closed support

The patent of the utility model relates to a closed support. What this supporting construction mainly included upper portion u type steel fiber concrete steel pipe and lower part prevents the pucking structure. Wherein upper portion u type steel fiber concrete steel pipe mainly is that to pour into the even steel fiber concrete of mix into u shaped steel intraductal, has improved the ability of steel pipe resistance to deformation. The pucking structure of preventing of lower part comprises antiarch roof beam, rubble and concrete floor, can effectively prevent the tunnel pucking. Two parts pass through high strength bolt to be connected, has constituteed the closed supporting construction who excels in. This structure atress is equitable, and the construction of being convenient for has broken through the difficult problem that there is stress concentration in traditional supporting construction, has improved the intensity of a country rock watch box greatly. This structure has good engineering application an